<template>
  <section class="todoapp">
    <!-- 除了驼峰, 还可以使用-转换链接 -->
    <TodoHeader @addTask="addTaskFn" :list="list"></TodoHeader>
    <TodoMain :list="showList" @delTask="delTaskFn"></TodoMain>
    <TodoFooter :list="showList" @showTask="showFn" @emptyTask="emptyTaskFn"></TodoFooter>
  </section>
</template>

<script>
// 1.0 样式引入
import "./styles/base.css";
import "./styles/index.css";

import TodoHeader from "./components/TodoHeader";
import TodoMain from "./components/TodoMain";
import TodoFooter from "./components/TodoFooter";

export default {
  components: {
    TodoHeader,
    TodoMain,
    TodoFooter,
  },
  data() {
    return {
      list: JSON.parse(localStorage.getItem('list')),
      getSel: "all",
    };
  },
  methods: {
    addTaskFn(task) {
      this.list.push({
        id: this.list.length === 0 ? 100 : this.list.at(-1).id + 1,
        name: task,
        isDone: false,
      });
    },
    delTaskFn(id) {
      this.list = this.list.filter((item) => item.id !== id);
    },
    showFn(str) {
      this.getSel = str;
    },
    emptyTaskFn(){
      this.list = this.list.filter((item) => !item.isDone)
    }
  },
  watch: {
    list: {
      deep: true,
      handler() {
        localStorage.setItem("list", JSON.stringify(this.list));
      },
    },
  },
  computed: {
    showList() {
      if (this.getSel === "yes") {
        return this.list.filter((item) => item.isDone);
      } else if (this.getSel === "no") {
        return this.list.filter((item) => !item.isDone);
      } else {
        return this.list;
      }
    },
  },
};
</script>